#left-links {
    text-align: center;
    font-size: 1.3em;
}

#side-btn {
    position: fixed;
    top: 20px;
    left: 0px;
    width: 70px;
    height: 50px;
    display: none;
    background: #eee;
    box-shadow: 0px 0px 10px 0;
    border: transparent;
    border-radius: 0px 24px 24px 0px;
}

#side-flag {
    position: absolute;
    display: none;
}

#side-control {
    display: inline-block;
    font-size: 3em;
    width: 50px;
    cursor: pointer;
    line-height: 1em;
}

#dark-btn {
    border: none;
    outline: none;
    background: transparent;
    cursor: pointer;
}

/* 移动端适配 */
@media screen and (max-width: 700px) {
    #side-btn {
        display: block;
        z-index: 114;
    }
}